Question: What is the active ingredient pharmaceutical product in erythromycin?
Paraphrase: What is the active ingredient in an erythromycin perscription?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q213511 wdt:P3780 ?obj . ?obj wdt:P31 wd:Q28885102 } 
Answer: EryPed, Erythrocin, Erythrocin Stearate, Ery-Tab, Erygel, PCE, Ery, Emcin Clear, Emgel, E.E.S.